1. Field of the Invention
The present invention relates to an electrical connector, and more particularly to an electrical connector having a cap-like fixing member fitted around the outer surface of terminal receiving chambers for receiving male or female terminals.
2. Statement of the Prior Art
Referring to FIGS. 4A and 4B, one example of prior art electrical connectors of the type that have fixing members provided therewith will be described.
FIGS. 4A and 4B are exploded perspective views of prior art electrical connectors each having a fixing member.
As shown in the figures, the prior art electrical connector (hereinafter, simply referred to as a connector) comprises a female connector 3 having terminal receiving chambers 5 for receiving female terminals (not shown) and a separate cap-like fixing member 6A, or a male connector 4 having terminal receiving chambers 5 for receiving male terminals (not shown) and a separate cap-like fixing member 6B. In the female connector 3, a sealing ring 12 is initially fitted around the integral outer surface of a pair of terminal receiving chambers 5 at an intermediate position 17 thereof, and the fixing member 6A is then fitted around the integral outer surface of the pair of terminal receiving chambers 5 at the front end thereof for preventing the withdrawal of the sealing ring 12. In addition, the fixing member 6A functions to press and hold, by the action of the inner surface thereof, the free ends of resilient locking pieces 7 for locking terminals inserted into the terminal receiving chambers 5 (which are cantilever-like locking pieces each constructed so as to be secured to the rearward portion of the associated terminal receiving chamber 5 at one end thereof, while being free, so as to function as a locking end, at the other end which is close to the front end of the terminal receiving chamber 5 for preventing the withdrawal of the inserted terminal). Thus, the fixing member 6A serves to effect the stable locking of the female terminals in position by means of the resilient locking pieces and also serves to increase the mechanical strength at the front portions of the pair of terminal receiving chambers 5.
Similarly, in the male connector 4, the fixing member 6B is fitted around the outer surface of the pair of terminal receiving chambers 5 in which male terminals are already fitted, respectively, at the front end thereof and presses and holds resilient locking pieces 7, which are the same as those provided on the female connector 3. Thus, the fixing member 6B also serves to effect the stable locking of the male terminals in positions by means of the resilient pieces 7, as well as serving to increase the mechanical strength at the front portions of the pair of terminal receiving chambers 5.
In the drawings, reference numeral 15 denotes a locking piece for locking the fixing members 6A and 6B to the female and male connectors 3, 4, respectively, reference numeral 16 denotes a locking pawl, provided for the same purpose as that described above, reference numeral 13 denotes an operation tang used to hold the fixing member 6B when the fixing member 6B is fitted around or removed from the terminal receiving chambers 5, and reference numeral 20 denotes a hole through which the male terminal is inserted into the female terminal housing.
In the respective fixing members 6A, 6B, the locking pawls 16 formed on the inner surfaces of the fixing members function as primary locking mechanisms for temporarily locking the fixing members 6A, 6B around the outer surface of the terminal receiving chambers 5 before terminals are inserted thereinto, and the locking pieces 15 also formed on the inner surfaces of the respective fixing members 6A, 6B so as to be brought into engagement with notches 5A formed in the respective terminal receiving chambers 5 function as secondary locking mechanisms. Thus, the fixing members 6A, 6B are fully locked around the outer surface of the terminal receiving chambers 5 by means of these two locking mechanisms.
In a connector comprising the above described parts having the fixing members 6A, 6B, terminals are designed to be fitted in the respective terminal receiving chambers 5 with a certain amount of play being provided therebetween in order to facilitate the insertion of the terminals from the rear of the respective terminal receiving chambers 5. Thus, the terminals are inevitably loose when they are inserted in the terminal receiving chambers 5 due to the play, and since the alignment between the relevant terminals is lost when they are loose, it is not possible to efficiently connect the female and male connectors. In addition, in a case where the female and male connectors are forcibly connected to each other under a condition in which the terminals in the female and male connectors are not in good alignment with each other, the terminals are damaged and deformed, resulting in the deterioration of the electrical performance thereof.
Furthermore, in the above described connectors having the fixing members 6A, 6B for effecting the stable locking of terminals via the resilient locking pieces 7 by pressing and holding the free ends of the latter by the action of the inner surface of the fixing members, even when the terminals are not fully inserted, resulting in the incomplete engagement between the resilient locking pieces 7 and the terminals so inserted, the fixing members 6A, 6B are fitted around the outer surface of the terminal receiving chambers 5 accordingly. Thus, with this construction, it is not possible to detect a terminal insertion error, and hence there is a risk of producing faulty connections.